Room environments are challenging for transmission of information via acoustic signals. This is due to the extreme multi-path nature of an impulse response of the room from the transmission source (loudspeaker) to wherever the capture device (microphone) resides. Although humans are well adapted for this environment, traditional forms of communications (e.g. using acoustic tones and pulses) have difficulty operating reliably in such an environment. As an example, direct path sound may be as much as 20 dB below a sum of reverberant sound (non-direct path sound) when the loudspeaker and the microphone are separated by 30 feet in a typical conference room.